Fire alarm question

DPhilpott · Mar 13, 2012

Hi guys,

I've fitted a fairly standard fire alarm system and commisioned it.. All fine. Customer has a window they would like to be opened to vent smoke in fire situation. The panel has the auxilliary switches. Is it going to be possible to run a standard 24v window actuator(powered from its own source) through the fire alarm relay? Thanks guys

telectrix · Mar 13, 2012

opening a window in a fire situation could fan the fire and make it spread quicker.

needasparks · Mar 13, 2012

Sometimes you can't see the wood for the tree's, more so when its on fire.

a1guvner · Mar 14, 2012

On new build flats we fit smoke vents in the roof which opens on the activation of the fire alarm, but only in the communal area,

DPhilpott · Mar 14, 2012

Well i pointed this out... Fire brigade open door on ground floor and window opens on top floor (communal hallway) = bigger fire. Customer spec though. Although, that does create a new question.. Do i mention this on my fire alarm cert?

telectrix · Mar 14, 2012

refuse to do it on the grounds that it's dangerous.

DPhilpott · Mar 14, 2012

I mite email local fire officer and double check his stance

telectrix · Mar 14, 2012

best way. if he vetoes the idea, then you've got official back up

alarm man · Mar 14, 2012

DPhilpott said:
Well i pointed this out... Fire brigade open door on ground floor and window opens on top floor (communal hallway) = bigger fire. Customer spec though. Although, that does create a new question.. Do i mention this on my fire alarm cert?

its better to vent in hallways etc imo,can help make exists easier and the fact its the smoke that kills more than the fire,tho i presume the spec has been ok'd by the insurance co,tho as you say ask the fire officer he holds the power.

tazz · Mar 17, 2012

This one comes up so many times, Ok local authorities usually require opening of vents stating smoke is the biggest danger. So before you do anything get approved conformation.
Best method in any case is to fit 3 way vent switch stating "off" "auto" "on" its a simple wiring job using off the shelf boxes and switches from local electrical wholesalers.
The idea of this method is when fire brigade are on site the can close vent until fire is out, then vent the smoke from building. If you need any wiring details just ask

DPhilpott · Mar 17, 2012

tazz said:
This one comes up so many times, Ok local authorities usually require opening of vents stating smoke is the biggest danger. So before you do anything get approved conformation.
Best method in any case is to fit 3 way vent switch stating "off" "auto" "on" its a simple wiring job using off the shelf boxes and switches from local electrical wholesalers.
The idea of this method is when fire brigade are on site the can close vent until fire is out, then vent the smoke from building. If you need any wiring details just ask

That sounds like a reasonable option. Can i then make a standard 24v actuator do this? Or do i need the one with seperate relay etc? The switches on the panel are dry but i can run a supply from db if its going to work correctly?
Thanks again

tazz · Mar 17, 2012

You need check the current draw from actuator, should only be 40ma at 24v.
Most fire panels have aux 24v outputs rated at 1A so you should be able to used aux to power it.

I have attached wiring diagram which might explain.